It also doesn't help that some individuals spread the idea that having good experiences in 1v1 and 4v4 are mutually exclusive and that everything should focus on competitive 1v1 when players in those game modes represent a small fraction of total base.
I don't think there's any way to balance 4v4 for the simple reason that it's dominated by people who just have very little idea how to play the game and just want to see big battles without having to be responsible for winning.
I slugged my way to #1 in USF random once and my teammates never actually got any noticeably better the whole time. Every match was basically a coin toss.
The closer you get to 1v1, the less of a variability skill becomes. Some things are definitely team-based and need to balanced on that basis (certain commanders and abilities such as command tanks generally), but that can be done with 2v2 in mind.